The present disclosure relates to a vibrator.
A vibrator, a component converting electrical energy into mechanical vibrations using the principle of the generation of electromagnetic force, is mounted in a mobile phone or the like to silently notify a user of call reception by transferring vibrations thereto.
Meanwhile, in accordance with the rapid growth in the mobile phone market and the trend toward the addition of functionality to mobile phones, mobile phone components have been required to be miniaturized and to have high quality. In this situation, the demand for the development of the vibrators having a new structure capable of overcoming the disadvantages of existing vibrators and having significantly improved quality has increased.
In addition, as the release of smartphones, among mobile phones, has rapidly increased, a touchscreen scheme has been adopted for use therewith, such that vibrators have been increasingly used in order to generate vibrations at the time of a touch interaction with a touchscreen.
Levels of performance required in the vibrations generated at the time of touching the touchscreen are as follows. First, since the number of vibrations generated at the time of touching the touchscreen is greater than that of vibrations generated at the time of call reception, an operation lifespan should be increased. Secondly, in order to increase user satisfaction when a user encounters vibrations at the time of touching the touchscreen, a response speed of the vibrations should be increased in accordance with a touch speed of the touchscreen.
In addition, a piezo haptic actuator has been used as products capable of implementing such levels of performance. Such a piezo haptic actuator uses a principle of an inverse piezoelectric effect by which displacement is generated when a voltage is applied to a piezoelectric element, for example, a principle of allowing a weight of a mover to be moved by the generated displacement to generate vibrational force.
A vibrator having the above-mentioned structure has the following features. A bandwidth of a frequency capable of obtaining a predetermined level or more of vibrational force is wide, such that stable vibration characteristics may be implemented, and vibrations having low and high frequencies rather than a single frequency in a predetermined frequency range may be variously used. In addition, since the vibrator may implement rapid operation response characteristics, it may be appropriate for implementing haptic vibrations of a mobile device such as a mobile phone, or the like.
Meanwhile, the piezoelectric element generally has a rectangular parallelepiped shape in which a length thereof is greater than a width thereof. In this case, since the length of the piezoelectric element should be relatively long in order to secure displacement and vibrations, an overall length of the vibrator may be increased and the piezoelectric element may be vulnerable to impacts due to being dropped.
Further, since the overall shape of the vibrator is a rectangular parallelepiped, the entire volume thereof is increased, such that it is not appropriate for miniaturization of components.